Block descriptions

UM0804

12/25

Doc ID 16303 Rev 2

6.9

General power supply

From a 5 V external AC/DC regulator power source, this block, generates all the required

voltages as follows:

●

1.2 V (Switching regulator PM6641) to supply the internal logic of the SPEAr300

●

1.8 V (Switching regulator PM6641) for the DDR2 memory.

●

2.5 V (LDO regulator) for the analog portion of SPEAr300

●

3.3 V (Switching regulator PM6641) to supply the other interfaces.

A power monitor is also present to provide the general reset of the board.

6.10

General-purpose I/Os

Eight general-purpose I/Os are present on the board. The eight lines are connected to the

J7 connector. The same connector also has GND and 3.3V pins available.

Note:

For the connector pinout, refer to the schematic drawing available on www.st.com/spear.

6.11

Reset switch

A manual reset switch (SW1) is available on the top side of the board.

6.12

LCD Interface

The J8 connector (p/n SFM-125-02-S-D manufacturer Samtec) is provided to allow you to

connect an LCD daughter board. It mates with TFM-125-02-S-D.

The following signals are available on this connector:

●

All the LCD interface signals

●

Two analog inputs (A/D)

●

+5 V

●

GND

Note:

For the connector pinout, refer to the schematic drawing

6.13

SDIO interface

A standard SDIO connector is also provided on the board (J5).